In this investigation, the e®ects of carbon nanotube (CNT) shape and distribution on nanocomposite failure are investigated. To achieve our goals, nanocomposites consisting of straight and sinusoidal CNTs with uniform and nonuniform distributions have been modeled. Failure of these nanocomposites is investigated using¯nite element simulations and micromechanics models. Initially, straight CNT-reinforced polymer is simulated and the stress-strain diagram for this nanocomposite is obtained. To validate our models, the simulation results of this nanocomposite are compared with those found in the literature. Then, sinusoidal CNT-reinforced polymers with uniform and nonuniform CNT distributions are modeled. The results are compared to determine the in°uence of CNT shape and distribution on nanocomposite failure mechanisms.